One aspect of the vehicle that has changed little is the swing-out door. The swing-out door is suspended from the vehicle body using conventional single-axis hinges. Each single-axis hinge comprises two leaves; a stationary leaf that is usually mounted on a forward portion of a doorjamb, and a hinge leaf that is usually mounted on a forward portion of a door edge. Each leaf comprises one or more knuckles which have coaxial through bores. The knuckles of two leaves are interleaved such that the through bores are placed in coaxial alignment. The leaves are rotatably joined together with a hinge pin extending through the bores.
The conventional single-axis hinge permits rotation within one plane. As the door is opened, the rear door edge swings out from the side of the vehicle in a substantially horizontal plane, whereby a space for stepping-in and stepping-out is formed between the rear door edge and the vehicle body. A major issue with swing-out doors is the situation of tight parking spaces with little room for the door to swing open to allow ingress and egress. Also, the potential for damage to an adjacent vehicle is a persistent problem resulting in the inevitable door ding.
Other door opening configurations have been tried, such as sliding, gull wing, and vertical-lift doors. Sliding doors are popular on vans, but not vehicles. The single-axis hinges of the gull wing door are mounted along the upper door edge, the door forming a portion of the roof, and permits rotation of the door above the vehicle; a design made famous by DeLorian Motor Company. The single-axis hinge of the vertical-lift door, which is also known as lambo, scissors, or jack-knife doors, is mounted in the forward upper door corner which permits door rotation substantially within a vertical plane defined by the door; a design made famous by Lamborghini.
The advantages of the vertical-lift door are both functional and aesthetic. Since the rotation of the door is upward and not sideways, as with the common swing-out door, ingress and egress is greatly facilitated in closely-spaced parking situations. The vertical-lift door eliminates the potential of banging the door against an object located to the side of the vehicle. The vertical-lift door also adds a sense of style and luxury to the vehicle.
For the most part, vertical-lift doors have been available only on expensive luxury performance vehicles and vehicles assembled from a kit by the consumer. These vehicles have door and door jam configurations, single-axis hinges, and latching mechanisms specifically designed into the vehicle to permit the door to open vertically.
Many vehicle enthusiasts consider it highly desirable to incorporate exotic features into their ordinary stock vehicles. The vertical-lift door is one such feature that has, for the most part, been out of reach of the aftermarket enthusiast. Retrofitting the conventional door to operate as a vertical-lift door is difficult to impossible due in part to door and vehicle body style. Many vehicle body styles incorporate doors with contoured surfaces that would collide with the vehicle body if opened as a vertical-lift door.
In some vehicle body styles, the bottom edge of the door undercuts the vehicle body and, therefore, would prevent vertical rotation of the door. Other vehicle body styles incorporate roof structures that overhang the top edge of the door, precluding vertical rotation of the door.
These and other issues hinder the availability of aftermarket components that would permit the vehicle enthusiast to retrofit the conventional swing-out door to operate as a vertical-lift door. These issues also hinder the vehicle manufacturers from incorporating vertical-lift doors in vehicles without requiring major redesign of the current vehicle body styles which may or may not be aesthetically pleasing to the customer.
It would, therefore, be highly desirable to have components and assemblies that would provide vehicle manufacturers and aftermarket enthusiasts the ability to incorporate the motion of the vertical-lift door in currently designed vehicles without major modification to the vehicle body or door structures.